Sh2-135, the brightest patch of nebulosity in the lower left part of this image, is a rarely photographed emission nebula in southern Cepheus, located between ζ and δ Cephei. It is an H II region linked to a dark nebula of interstellar dust which shows a pronounced ionization front and is expanding. A model that can well explain the situation is the so-called blister model: According to this model, the ionized gas is blown away from the front of ionization as a result of the interaction between the H II region and the adjacent molecular cloud. The star responsible for the ionization of the gas is of spectral type O9, distance estimates provide a value of about 6200 light-years. Numerous sources of infrared radiation have been detected around this nebula, thus indicating the presence of recent star formation processes.

There are many more nebulae bright and dark visible within this photograph. In fact, nearly the whole image has a background of faint emission nebulosity. Major parts bear the designations Lynds' Bright Nebula (LBN) 491, 492 and 493. Also visible are many dark nebulae in-between.

Sharpless 135, which this image is part of.